Honestly it's probably the same stuff every other company uses but Apple is very well known for sourcing Black versions of everything for their internals
So they probably just said "We need material for our Headphone Diaphragms.... Can we get that in Black?"
DanielF823 t1_iraghuc wrote
Reply to What the material of Airpods Max's diaphragm? The black color makes it look super cool by GreenNerve
Honestly it's probably the same stuff every other company uses but Apple is very well known for sourcing Black versions of everything for their internals
So they probably just said "We need material for our Headphone Diaphragms.... Can we get that in Black?"